Mass spectrometry is a commonly-used technique to identify the chemical substances that are present in a sample of material. In this technique, a mass spectrometer breaks the sample up into charged particles by ionizing the sample. The mass spectrometer then identifies the ratio of mass to charge for each particle. The mass spectrometer also measures the amount of material associated with each particle. The amount of material thus determined relates to an intensity dimension of the measurement.
More specifically, in one approach, each data point (or data cell) measured by the mass spectrometer comprises three data values: a retention time (RT) data value, a mass-to-charge (m/z) data value, and an intensity (I) data value. The RT data value relates to a time at which the mass spectrometer makes a plurality of mass-to-charge measurements and intensity measurements. The m/z data value refers to an individual m/z measurement for a particular RT data value. And the intensity data value refers to an individual intensity measurement for a particular RT data value and m/z data value. Upon recording plural such data points, the mass spectrometer can construct liquid chromatography-mass spectrometry (LC/MS) spectra. The LC/MS spectra can be represented by a first axis corresponding to the retention time, a second axis corresponding to the mass-to-charge ratio, and a third axis corresponding to intensity. Such LC/MS spectra typically reveal a few dramatic intensity spikes in an otherwise baseline of low-level noise.
A typical mass spectrometer produces a large quantity of the above-described mass spectrometry data. For instance, a mass spectrometer can easily produce a volume of mass spectrometry data in the gigabyte range for a single measurement run. This factor introduces various challenges in the effective manipulation of the data. Such manipulation encompasses the storage, retrieval, transfer, and processing of the mass spectrometry data.
Future increases in the precision and efficiency of mass spectrometers can be expected to compound the above-noted challenges, e.g., by potentially providing the capacity to generate even greater volumes of mass spectrometry data over decreasing spans of time.